Brake mechanism.



T. I. DUFFY.

v BRAKE MECHANISM.

APPLICATION FILED 00T. 28,1912.

1,076,562, Patented oct.21,x1913.

. l' lllllLi /f v n HHH f operating on in elevationand partly in section, with parts UNITED STATES PATENT OFFICE.

THOMAS I. DUFFY, or

emesso, ILLNoIs, AssIGNoR To E. c. SALES co., or omesso,

ILLINOIS, CCRPORTION 0F ILLINOIS.

BRAKE MEeHANIsM.

www.;

Bpe'cication of Letters Patent.

Patented Oct. 21, 1913.

Application led October 28,' 1912. Serial No. 728,216.

To' all whom it may concern Be it known that I, TH'oMAs I. DUFFY, a citizen 'of the UnitedStates, and a resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Im rovements in Brake Mechanism; and I do hereby declare that the following is a full, clear, and exact description thereo reference bei g had to the accompanying drawings.V andi to the characters of reference marked thereon, which form a part of this specification.

This invent-ion relates to improvementslin brake mechanism more especlally adapted for rear or driving axles of motor vehicles and for analogous uses, and the invention consists in the matter hereinafter set forth and more particularlypointed out in the appended claims. e

Amon the objects of the invention is to provide lmprovements in brake mechanism embracing internal and external brake bands the braking faces of a single brake drum, with means for operating said bands.

A further object of the invention is to provide means for operating an external rake band to tighten the same about the external braking face of the drum.

Another object4 is to provide an improved brake band adapted for use as an internal or external band designed to equalize the braking pressure transversely across the braking face or faces of the drum.

In the drawings: Figure 1 is a view partly broken away, of a brake mechanism adapted for. a rear or drivin wheel of a motor driven vehicle emb ing my invention. Fi 2 is an elevation ofythe operating mechanismfor the external brake band. Fig. 3 is a side elevation showing the means for operating both the external and internal brake bands. Fig. 4 is a view similar to Fig. 3 showing thel parts in changed positions. Fig. 5 is a detail illustrating the the external brake bands.

The brake mechanism is herein shown as applied to a full-tioating type 0f. rear or driving wheel axle for motor driven vehicles, wherein the hub 9 is mounted to rotate on the spindle 11 that is suitably fixed to the axle casing or housing 10 and is driven by suitable `connection with the live axle or driving shaft 12 in any suitable manner, as for instance,.like the construction sho'wn in y co-pending application for U. s. Lettere atene, seriel Ne. 728,214 filed on the28th day of October, 1912.

14 designates the brake drum which is attacll'ed to the hub 9, as by means of the bolts 15, the drum being provided with the usual cy indric flange 16 concentric with the driving sha t and extending inwardly from the hub. Y n the present construction, the inner and outer surfaces of the said flange 16 constitute the internal and external braking faces, respectively, ofI the drum.

18, 19 aeeignete the internal and external brake bands, respectively, the former surrounding, and' the latter contained within the flange of the brake drum. The said brake bands are provided on their braking sides with the usual fabric or other flexible friction faces 20, 21, respectively, adapted for direct contact with the braking faces of the drum. y

The .internal brake band is provided at one sid'e of the axis of the drum with a loop or loops 23 through which extends an anchor stud 24 that is fitted within a boss 25 which is formed on the torque arm 26. Said torque arm is fixedly attached, as by means of screw bolts 27, to the flange 28 made integral, as herein shown, with the housing 10 of the axle. The external brake ban-d .is in like manner provided with a loop or loops 29 through which extends the anchor stud 30 that is, in like manner, carried by a boss 31 formed on an extension of the torque arm 26.

The ends of the internal brake band are provided with lugs or fittings 35 which are riveted or otherwise secured to the said band. As herein shown they comprise curved base portions 36 through which the fastening rivets extend, and inwardly turned portions 37 having proximate smooth mit) side ribs shown in Figs. fi and 4. -ln order to relieve the attaching rivets ot` shearing stresses. which occur when the brake is cx pand-ed outwardly, said lugs are provided with lip-; Vt() which overlap the end edges of' the brake band in the manner shown in ltig. l. yl`he said internal brake band is expanded o||t\\'ardly against the inner braking snrlace otl the drum flangeby means ol' a rocking expander member or cam l2 that is attached to or formed on a rock shaft It which is roekingly mounted in a boss or sleeve 44 carried by the adjacent end ot the torque arm. The said lugs are adapted to be held up against the expander` member or cam 42, when the, internal brake band is in its closed or non-braking position, by means of a C-shaped spring 45 engaging' at its ends the outer or remote .faces of the inturned portions 3T of the inner brake baud lugs 35.

The internal brake band is shown in Fig. 3 in its inoperative or non-braking position and, at this time, the spring l5 holds the lugs of' the band closely up against; the expander member so as to prevent the parts rattling. ln Fig. 4, the expander member or cam is shown as angularly adjusted to expand the internal brake band, such expansion occurring by reason of the oblong rectangular` cross section of the expander member.

Referring now to the manner ot' operating the external brake band to bring the. same against the external braking face. ot' the drum, the same is made as follows: designates a fitting or lug that is attached to one end of the external brake band. It comprises a base portion 5l and outstanding flanges or arms 52, 52, which are laterally separated to constitute, in etl'ect, a divided lug. Said flanges or arms 52 are provided with transversely registering openings 53. Carried by the other end of said band is a fitting 55 that fits between the flanges or arms and is provided with an opening 5ft adapted to register with the openings 53 ot' the said arms or flanges. 'lhe said fitting 55 is herein shown as attached to the brake band by means of a stud 58 which is screwthreaded and extends through a lug 59, the base (3() of which is attached to the other end of the external brake band, the said stud being adjusted to the lug 59 by means of the nuts (il, G1 screw-thrcaded thereto on opposite sides of the lug and bearing against the latter. The openings in said fittings 50, 55 are provided with straight or parallel faces G3, (i4, respectively, which oppose each other when the parts are assembled, as most clearly shown in Figs. 3 and 4. These faces of said fittings are adapted for engagement by a rocking member which extends transversely through the openings 53, 56. The said rocking member is of oblong rectangular cross section and one side thereof engages the flat face of one. fitting, while the other side thereof engages the flat or straight faces ofthe other fitting. The parts are normally maintained with the straight faces i555, (34 in engagement with the rocking member (35. as most clearly shown in Fig. 4t, b v a. suitable spring device to prevent the parts from rattling. rl`he spring device herein shown consists ot' a spiral expansion spring (33 that is interposed between the fitting 50 and the closed end of the loop member (it) carried by the fitting 50, the loop meinbm being herein shown as Consisting ot'a flat strip ot general U-shape With its terminals Tt) carried through the openings in the side arms or flanges ot the fitting o0 and bent backwardly about the same. The said spring (38 is held in position by means' ot' a bolt 72 which extends through an opening in the closed end of the loop and is screw-threaded into the'fitting member 50. lVhcn the expander member G5 is turned to the position indicated in Fig. 3, the external. brake band is pressed against the eX- ternal face of the drum, against the compression ofl the spring 09, as shown in Fig.

il and. when braking pressure is released, the said spring (SS restores the brake band to its non-braking position and brings up the working faces ot' the fittings 50 and 55 against the rocking or contracter member so as to prevent the parts rattling.

The screw-threaded stud 58, by which the fitting 55 is attached to one end of the brake band, constitutes means whereby the working faces of the brake band fittings may be adjusted toward and from each other, and therel'iy properly adjust the band to the drum. 'lhe said rocking member 65 is formed on or is carried by a short rrock shaft that is roekingly mounted in a sleeve or boss 7G carried by or formed on an extension of the torque arm 26, as most clearly shown in Fig. 1.

The rock shaft 75 is provided with a fixed crank arm 7S which isconnected, as by a link 7i), with a. crank arm 80 that is fixed rigidly vto a tubular rock shaft 8l which surrounds and has bearing on the extended end of the rock shaft -l associated with the internal brake band. The said solid and tubular rock shafts are provided with crank arms 83 respectively, and the rock shafts are. in practice, made of a length to bring said crank arms or levers to the proper point l'or connection with the brake actuating levers. This construction is a simple one, enabling the internal and external bands of' the drum to be operated by rocking members that rock or rotate on the same axis. .\s ay further improven'ient in brake bands, l have herein shown each band as being slitted throughout almost the entire ternal braking length thereof, the slit 85 bein shown as located centrally of the band an extending longitudinally of the band from near the fitting member 50 at one end thereof adjacent to the lug 59 at the other end of the band. This construction enables the band to transversely adapt itself to the braking face of the drum, regardless of sli ht inaccuracies of fit between the parts. ere the brake band is made transversely inflexible it often occurs that the effective braking contact is along a comparatively narrow width of the band, so that the full braking effect is not realized.

I claim as my invention 1. A brake mechanism for motor vehicles comprising a drum provided with an external braking face, a brake band therearound, a slotted fitting attached to one end of said band, a fitting adjustably fixed to the other end of said band and overlapping the slotted fitting within the slot thereof, said fittings being provided with opposing faces at their overlapping parts, and a rocking contracter member between and acting directly on said faces.

2. A brake mechanism for motor vehicles comprising a drum provided with an external brake face, a brake band therearound, a slotted fitting attached to one end of said band, a fitting adjustably fixed to the other end of said band and overlapping the slotted fitting within the slot thereof, said fittings being provided with opposing faces at their overlapping parts, a rocking contracter member between and acting directly on said faces, and a spring acting on said fittings to normally hold said faces against the contrai-ter member.

3. A brake mechanism for.motor vehicles comprising a drum provided with an exface, a brake band therearound, a slotted fitting attached to one end of said band, a fitting overlapping the slotted fitting and provided with a screwthreaded stud, a lug attached to the other` end of the brake band and having an opening Athrough which the stud extends, with means for adjusting the stud on said lug, said fittings being provided at their overlapping parts with opposing faces and a rocking contracter member between and acting on Said faces to contract the band on the braking face of the drum.

4. A brake mechanism for motor vehiclesv comprising a drum provided with an external braking face, a brake band therearound, a slotted fitting attached to one end of said band, a fitting overlapping the slottedtting and provided with a screwthreaded stud, a lug attached to the other end of the brake band and having an opening through which the stud extends, with means for adjusting said stud on thevlug,

said fittings being provided at their overlapping parts with on osing faces, a rocking contracter member tween and acting on said faces to contract the band on the braking face of the drum, and a spring to normally hold said faces of the fittings against the contracter member.

5. A brake mechanism for motor vehicles comprising a drum provided with an external braking face, a brake band therearound, a slotted fitting attached to one end of said band, a fitting overlapping the slotted fitting and provided with a screwthreaded stud, a lug attached to the other end of the brake band and having an opening through which the stud extends, with means for adjusting the stud on said lug, said fittings being provided at their overlapping parts with opposing faces, a rocking contracter member between and acting on said faces to contract the band on the braking Nface of the drum, a U-shaped member carried by said slotted fitting, a bolt or stud extending through said U-shaped member and into the other fitting and a spring surrounding the bolt and interposed between said U-shaped member and said other fity ting.

6. A brake mechanism for motor vehicles comprising, in combination with a drum having internal and external brake faces, brake bands adapted to respectively co-act with said faces, rocking operating members between the ends of said bands for actuating them, a tubular shaft surrounding the rocking member of one band, said tubular shaft and the other rocking member being provided with crank arms, and a link connecting said arms.

7. A brake mechanism for motor vehicles comprising, in combination with a drum having internal and external brake faces, transversely divided bands adapted to respectively co-act with said faces, rocking operating members between the ends of the bands, the inner band being provided at its ends with fittings having op osing faces at the opposite sides of its roc ting member to co-act with said latter member, and the outer band being provided at its ends with overlapping fittings having at the opposite sides of its rocking member opposing faces to coact with its said rocking member, and means t0 simultaneously rock said members to expand the inner bands against and to close the outer band upon their respective brake faces.

8. In a brake mechanism, the combination with a brake drum having a brake face, of a brake band acting thereagainst comprising a transversely continuous flexible friction member of a width to extend across the brake face, and a backing member to which the friction member is attached composed sov of' a plurality of' imxgitudiuaily sepzuabie presence 0f two witnesses, this 18th day of paris wi'mieby braking pressure of the frici (kztmiwr, A. D. 191.9.

{im} mombur is equalize/i across the brake TUO-MS I DUFFY face, with meant: opvi'ziing 011 the brake! Mim to i'm'i'u iii against uid brake fano. l tui-sacs: A

In lvsimony that' ,I daim the {Gregoingl w. L. HALL,

:1r: my invention I aiix my Signature in tlm E. DOWLE. 

